Try this experiment with me. Go to a computer that you normally use and type in google.com/ads/preferences and hit enter, of course. And there, you will see just a hint of the profile that Google has built around you.

So in my case, the computer knows I'm male. It gives me a range for my age. It says I'm interested in song lyrics, in arts and culture - and clothing? That's interesting. All pretty innocuous stuff, right?

But Google has hundreds - probably thousands of data points with which they've built a much, much more detailed profile of me - and of you, too. We just don't know what that looks like/ And the question is, should we?

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RAZ: It's WEEKENDS on ALL THINGS CONSIDERED, from NPR News. I'm Guy Raz. And our cover story today: Google and privacy: what they know, what they don't know -and what's the big deal, anyway?

RYAN PAUL: If you're a Gmail user, they scan all of your email. If you're a YouTube user, they track all of the videos that you watch. So they have a large amount of information that they collect, that they aggregate, and that they use.

PAUL: This is really just part of what they track because they collect a lot of data on the back end, including search queries, which they keep for 18 months.

RAZ: Did you get that? Every search inquiry going back 18 months. Now, Google doesn't do this to spook you but rather, they say to help make your online experience better. The most obvious example, they say: targeted ads for things you buy or like.

But last week, Google stepped it up a notch by announcing a new privacy policy. All Google services like Gmail, YouTube and the Google search page will essentially track the way you use the Internet and send that information to one, central place.

You can opt out, but it means you can't use many of Google services - no Gmail, no YouTube, no Picasa. And if you have an Android phone, it basically becomes useless. [POST-BROADCAST CORRECTION: Users will still be able to see videos on YouTube, and Android phones will still have some functionality.] But Google insists there is nothing to fear. The company will protect your privacy. Here's Rachel Whetstone, Google's senior vice president for public policy.

RACHEL WHETSTONE: There's lots of different ways, magic little ways, that we can use information to improve your services - whether it's, you know, better spelling corrections; whether it's enabling you to, you know, add things from your Gmail to your calendar. Whatever it might be, it's all really about you, and it's about your information.

RAZ: But regardless, Google's new policy is getting a lot of not-so-good attention on Capitol Hill, in part because the company now allows kids as young as 13 to sign up for its services. That means Google can, in theory, build a profile of you over several decades.

All of this worries Massachusetts congressman Ed Markey. He's a senior Democrat on the House Subcommittee on Telecommunications and the Internet. But what he finds most objectionable is that users don't seem to have much say in all of this.

REP. ED MARKEY: It is imperative that users will be able to decide whether they want their information shared across the spectrum of Google's offerings, even if Google thinks they can make a profit by doing that.

RAZ: They're arguing that this is no different from what they've been doing all along. It's just simplifying it. They're saying that by doing this, they can make Google more consumer-friendly.

MARKEY: In my opinion, it's a precursor to a privacy nightmare. So let's just -

RAZ: How so?

MARKEY: Well, let's just take kids and teenagers. You know, for them, Googling is like breathing - they can't live without it. What business does Google have to not give a parent any rights whatsoever to opt out; to say, I don't want my kid's information to be aggregated this way, to market back to my kid.

RAZ: Well, Google presumably has a profile on Ed Markey and Guy Raz and everyone listening, people who use Google. They say, that doesn't matter. I mean, they may sell that information to marketers who will then target you, but the marketers don't know you. They don't know that that profile is connected to you or to me or to anyone else. Google says they protect that privacy.

MARKEY: They protect that privacy until they don't protect our privacy.

RAZ: You're saying you don't trust them.

MARKEY: What is the basis for that trust?

RAZ: Do you think that most people in America have kind of quietly resigned themselves to this reality? I mean, there isn't mass public protest over this new Google policy. Are you surprised?

MARKEY: I think that the only thing that is lacking is a full understanding by the public of the policy. I think there's a ticking time bomb here of public outrage about what Google and other companies are trying to do. They're saying, you can't understand it and as a result, we can get away with it.

But it's no different than what Wall Street said about derivatives - are credit to false swaps. Because you can't understand it, of course you don't care about it - until it comes back into their own home, till it destroys their job, huh? And so part of this debate is that - getting it elevated.

RAZ: Well, the train apparently has left the station. Google is planning on introducing this policy on March 1st. What are you planning to do in Congress to legislate either against this or other laws, to protect consumers against some of these things you're warning about?

MARKEY: My good friend congressman Joe Barton, from Texas, is going to introduce legislation with me - Ed Markey, from Boston - in order to ensure that there is a comprehensive child privacy bill. I think that once we win on children, we'll win on the other issues. But this debate should first of all, be about teenagers and children.

RAZ: That's Massachusetts congressman Ed Markey; he's a Democrat. He's also a senior member on the House Subcommittee on Telecommunications and the Internet, speaking about Google's new privacy policy. Congressman Markey, thanks.

MARKEY: Thank you for having me on.

RAZ: Joining us now for more on the upside, and the potential downside, of Google's new privacy policy is Chris Dawson. He's a contributing editor at ZDNet. Chris, welcome to the program.

CHRIS DAWSON: Thanks for having me.

RAZ: Also with us is Lori Andrews. She is the author of the book "I Know Who You Are and I Saw What You Did: Social Networks and the Death of Privacy." Lori, welcome to you as well.

LORI ANDREWS: Thanks.

RAZ: Let me start with you, Chris, because I know you consider yourself a Google junkie. You use Picasa and Gmail and YouTube, and all the other services they have to offer. And you are not at all bothered by these new privacy rules.

DAWSON: I'm not. Honestly, I've chosen to opt in. I find that it actually makes my life a lot easier.

RAZ: How does it make it easier for you? Give me an example.

DAWSON: Well, so let's say that I am searching for something. And an example I gave in an article I wrote was, I have been searching for electric guitars lately. So now, of course, everywhere I go on the Web, I have ads displayed to me for guitars ...

RAZ: OK.

DAWSON: ...because Google knows that I'm searching for it. I'm logged into my account. And so then, AdSense users - basically, independent websites that allow Google to place ads on their site - are going to display ads relevant to me. That's actually not a bad thing because I found a cheaper deal on my guitar.

Ultimately, though, I think what this can lead to is some much greater integration of services. So let's say on my Android phone, I have my GPS turned on. Google knows that every Friday night, I search for a pizza place. And I'm hoping that on my Android phone, my GPS will trigger an alert along about 4 o'clock that afternoon, when I happen to be driving past a well-reviewed pizza place that just happens to have a Google offer available - because now, these services are talking to each other.

ANDREWS: Well, assumptions are made about you based on what you do on the Web, and your digital self is getting to be more important than your offline self. So it may turn out that if other guitar players are more likely to renege on paying off their credit cards, that the next time Christopher searches for a credit card, he won't be able to get one at a good rate.

Sometimes, these things also push negative behavior. For example, when teens Gmail that they're thinking of committing suicide with X chemical, or talk about that on a Google suicide chat room, it turned out that AdWords actually popped up and said, call 1-800 now for a deal - two for one on that chemical.

RAZ: Hmm.

ANDREWS: Even the GPS. Think about Justice Sotomayor in this decision recently about GPS on your car. She says it tells a lot about you - your family associations; whether you're going to a psychiatrist, an abortion clinic. This is information we might want to keep private.

RAZ: But Lori, let's be clear. I mean, Google is building a profile of you, but they don't necessarily associate it with Lori Andrews, the person. I mean, they may be selling that information to advertisers, but the advertisers don't know who you are. They just know a profile of you.

ANDREWS: They do know who you are because Google now says it can change your screen name. So if I've got a YouTube account under one name, and then my Gmail account under something else, it will make it the same. So if you've ever Googled something that you don't want your spouse or boss to know - maybe for a divorce lawyer, a medical condition, or you've applied for another job - you could be watching a YouTube with your family and friends, and an ad based on this private email will appear, about this other job or your medical condition. That's a big problem.

RAZ: Chris, I guess you would argue that you put your trust and faith in a company like Google. You don't think that they are going to abuse your information. But to Lori's point, I mean, many people who use Google services, they really don't know the extent to which they're being tracked. They just don't know.

DAWSON: No, and that's entirely true. And there's a couple of things I'll point out here - is one, you're right; they do need to be thoroughly educated. They need to understand how they can turn off the tracking, how they can shut things down in such a way to maintain a degree of privacy.

ANDREWS: But Google has said if I turn off the GPS on my phone, they can still collect that information.

RAZ: Yeah.

ANDREWS: And so I think there's a kind of bait and switch going on, where we got addicted to all these services. It's kind of the same thing that happened in 2009 with Facebook - where if you look at the original things that Facebook told people, they said, we will only give your information to those people who you've indicated are your friends. And then in 2009, they made public who people's friends were in their pictures. They changed the rules after people had gotten addicted.

RAZ: You could argue that Google, Facebook - these companies now have databases to rival the Social Security Administration. I mean, they have a lot of data about individuals in the U.S., around the world. What is to stop Google from - you know, from one day in the future saying, all right, we're going to just dump this and sell it, and we don't care how people use it?

DAWSON: Money. Money is - this is what actually gives me some faith in Google - is, it's good old capitalism, because Google relies on the fact that there hasn't been a big public outcry over this. Overall, Google's done a pretty good job of being this trusted broker.

And the minute Google steps aside from that role, the minute that people do understand fully that now Google is just selling our data to the highest bidder, they lose that trust. And then they lose their ability to sell ads and generate ad revenue. All of a sudden, their business model goes away. So their billions of dollars a year in profits drop off the earth.

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